Information provision system

ABSTRACT

An information provision system mounted on a vehicle includes: a visual device configured to visually provide information to an occupant of the vehicle; and a controller configured to control the visual device. The controller is further configured to: cause the visual device to provide first information in a first period; cause the visual device to provide second information different from the first information in a second period later than the first period; and set at least one of a luminance and a saturation of the visual device in at least a part of an information switching period between the first period and the the second period to be lower than that in the first period and the second period.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. patent application Ser. No.17/086,746 filed Nov. 2, 2020 and claims priority to Japanese PatentApplication No. 2019-203301 filed on Nov. 8, 2019, the entire contentsof which are herein incorporated by reference.

BACKGROUND Technical Field

The present disclosure relates to an information provision systemmounted on a vehicle.

Background Art

Patent Literature 1 discloses an information display device used in anautomated driving vehicle. The information display device has a displaymeans that displays an image, and a display control means that causesthe display means to display an image of a steering wheel of the vehicleand an image of a human hand at the same time. The display control meanschanges at least one of the image of the steering wheel of the vehicleand the image of the human hand according to an automated driving level.

Patent Literature 2 discloses an information provision device for use ina vehicle. The information provision device presents whether automateddriving control is possible or not.

List of Related Art

-   Patent Literature 1: Japanese Laid-Open Patent Application    Publication No. JP-2015-182624-   Patent Literature 2: Japanese Laid-Open Patent Application    Publication No. JP-2018-185641

SUMMARY

As exemplified in the above-described Patent Literature 1, in recentyears, information is sometimes visually provided from an in-vehicledevice to an occupant (e.g., a driver). When the information changes,the information after the change is likely to be important to theoccupant, and thus it is desirable for the occupant to easily notice theinformation change. However, in the case of the technique described inPatent Literature 1, the image displayed on the display means merelychanges from a first image representing the information before thechange to a second image representing the information after the change.Therefore, it is difficult for the occupant to notice the informationchange.

An object of the present disclosure is to provide a technique that canvisually provide information to an occupant of a vehicle and facilitatethe occupant to more easily notice a change in information.

A first aspect of the present disclosure is directed to an informationprovision system mounted on a vehicle. The information provision systemincludes: a visual device configured to visually provide information toan occupant of the vehicle; and a controller configured to control thevisual device. The controller is further configured to: cause the visualdevice to provide first information in a first period; cause the visualdevice to provide second information different from the firstinformation in a second period later than the first period; and set atleast one of a luminance and a saturation of the visual device in atleast a part of an information switching period between the first periodand the the second period to be lower than that in the first period andthe second period.

A second aspect of the present disclosure further has the followingfeature in addition to the first aspect. The visual device is installedon a dashboard of the vehicle.

A third aspect of the present disclosure further has the followingfeature in addition to the first or second aspect. The visual devicerepresents the first information in a first color and represents thesecond information in a second color different from the first color.

A fourth aspect of the present disclosure further has the followingfeature in addition to any one of the first to third aspects. Thevehicle is an automated driving vehicle that performs automated driving.

A fifth aspect of the present disclosure further has the followingfeature in addition to the fourth aspect. One of the first informationand the second information is information demanding of a driver of thevehicle to grab a steering wheel during the automated driving. Anotherof the first information and the second information is informationnotifying that the driver is allowed to get hands off of the steeringwheel during the automated driving.

A sixth aspect of the present disclosure further has the followingfeature in addition to any one of the first to fourth aspects. Inresponse to a trigger, the controller switches the information providedthrough the visual device from the first information to the secondinformation. The trigger includes a change in driving environment thatrequires attention of a driver of the vehicle.

A seventh aspect of the present disclosure further has the followingfeature in addition to the sixth aspect. The trigger includes at leastone of a change in an operation required for the driver, a change in anautomated driving level of the vehicle, activation of driving assistcontrol that assists driving of the vehicle, detection of a previousstage of the activation of the driving assist control, start of apreceding vehicle, and approach of a surrounding vehicle.

An eighth aspect of the present disclosure is directed to an informationprovision system mounted on a vehicle. The information provision systemincludes: a visual device configured to visually provide information toan occupant of the vehicle; and a controller configured to control thevisual device. When an operation expected of a driver of the vehicle isnot performed by the driver, the controller causes the visual device toblink.

According to the first to seventh aspects of the present disclosure, theinformation provision system provides information to the occupant of thevehicle through the visual device. The first information is provided inthe first period, and the second information is provided in the secondperiod later than the first period. In the information switching periodbetween the first period and the second period, the information switchesfrom the first information to the second information. In at least a partof the information switching period, the information provision systemsets at least one of the luminance and the saturation of the visualdevice to be lower than that in the first period and the second period.In other words, the information provision system temporarily decreasesat least one of the luminance and the saturation of the visual deviceduring the information switching period. At this time, due to a visualproperty of human, the occupant of the vehicle is more likely to giveclose attention to the visual device. As a result, the occupant of thevehicle can easily notice the change in information provided through thevisual device.

According to the eighth aspect of the present disclosure, when theoperation expected of the driver is not performed by the driver, theinformation provision system causes the visual device to blink. Theblinking of the visual device applies stimulus to the driver's vision.It is thus possible to urge the driver to pay attention.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a conceptual diagram schematically showing a vehicle and aninformation provision system according to a first embodiment of thepresent disclosure;

FIG. 2 is a diagram for explaining an example of a visual device in thefirst embodiment of the present disclosure;

FIG. 3 is a diagram for explaining another example of the visual devicein the first embodiment of the present disclosure;

FIG. 4 is a diagram for explaining still another example of the visualdevice in the first embodiment of the present disclosure;

FIG. 5 is a diagram for explaining still another example of the visualdevice in the first embodiment of the present disclosure;

FIG. 6 is a conceptual diagram for explaining information switchingprocessing according to the first embodiment of the present disclosure;

FIG. 7 is a conceptual diagram for explaining a modification example ofthe information switching processing according to the first embodimentof the present disclosure;

FIG. 8 is a flow chart summarizing information provision processing andthe information switching processing according to the first embodimentof the present disclosure;

FIG. 9 is a flow chart showing a concrete example of the informationprovision processing and the information switching processing accordingto the first embodiment of the present disclosure;

FIG. 10 is a flow chart showing a concrete example of the informationprovision processing and the information switching processing accordingto the first embodiment of the present disclosure; and

FIG. 11 is a flow chart showing the information provision processingaccording to a second embodiment of the present disclosure.

DETAILED DESCRIPTION

Embodiments of the present disclosure will be described below withreference to the attached drawings.

1. First Embodiment 1-1. Vehicle Control System

FIG. 1 is a conceptual diagram schematically showing a vehicle 1according to a first embodiment. A vehicle control system 10 forcontrolling the vehicle 1 is mounted on the vehicle 1. The vehicle 1 maybe an automated driving vehicle that performs automated driving.

The vehicle control system 10 includes a sensor 20. For example, thesensor 20 includes a position sensor for detecting a position and anorientation of the vehicle 1, a surrounding situation sensor fordetecting a situation around the vehicle 1, a vehicle state sensor fordetecting a state of the vehicle 1, and a driver monitor for detecting astate of a driver of the vehicle 1. As the position sensor, a GPS(Global Positioning System) sensor is exemplified. As the surroundingsituation sensor, a camera, a LIDAR (Laser Imaging Detection andRanging), a radar, and the like are exemplified. As the vehicle statesensor, a vehicle speed sensor, a yaw rate sensor, a lateralacceleration sensor, a steering angle sensor, a steering torque sensor,an accelerator pedal sensor, a brake sensor, and the like areexemplified. As the driver monitor, a steering wheel touch sensor, acamera, and the like are exemplified.

Based on a result of detection by the sensor 20, the vehicle controlsystem 10 acquires “driving environment information” indicating adriving environment for the vehicle 1. For example, the drivingenvironment information includes position information, surroundingsituation information, vehicle state information, driver stateinformation, and the like.

The position information is information indicating the position and theorientation of the vehicle 1 and is acquired from a result of detectionby the position sensor.

The surrounding situation information is information indicating thesituation around the vehicle 1 and is acquired from a result ofdetection by the surrounding situation sensor. Typically, thesurrounding situation information includes a relative position and arelative velocity of an object around the vehicle 1. As the objectaround the vehicle 1, a surrounding vehicle (a preceding vehicle, afollowing vehicle, and the like), a pedestrian, a roadside structure, awhite line, and the like are exemplified.

The vehicle state information is information indicating the state of thevehicle 1 and is acquired from a result of detection by the vehiclestate sensor.

The driver state information is information indicating the state of thedriver and is acquired from a result of detection by the driver monitor.For example, the driver state information indicates whether the drivergrabs a steering wheel or gets hands off of the steering wheel.

The vehicle control system 10 executes “vehicle travel control” thatcontrols at least one of steering, acceleration, and deceleration of thevehicle 1 based on the driving environment information.

An example of the vehicle travel control is “automated driving control”when the vehicle 1 is an automated driving vehicle. For example, thevehicle control system 10 generates a target trajectory including atleast a target position of the vehicle 1, based on map information andthe driving environment information. The target trajectory may furtherinclude a target speed of the vehicle 1. The vehicle control system 10controls the steering, the acceleration, and the deceleration so thatthe vehicle 1 follows the target trajectory.

During the automated driving of the vehicle 1 (i.e., the automateddriving vehicle), the vehicle control system 10 may demand of the driverto “hands-on (HANDS-ON)”. The hands-on means that the driver grabs thesteering wheel during the automated driving. A zone in which thehands-on is demanded is hereinafter referred to as a “hands-on zone.”For example, based on the surrounding situation information, the vehiclecontrol system 10 sets a zone where the automated driving control isdifficult as the hands-on zone. As another example, the hands-on zonemay be predetermined. In this case, the vehicle control system 10 canrecognize the hands-on zone based on the map information.

On the other hand, “hands-off (HANDS-OFF)” means that the driver isallowed to get hands off of the steering wheel during the automateddriving. In zones other than the hands-on zone described above, thedriver may be in the hands-off state, i.e., get hands off of thesteering wheel.

Another example of the vehicle travel control is “driving assistcontrol” that assists driving of the vehicle 1 by the driver. Thedriving assist control is exemplified by collision avoidance control,lane departure suppression control, and the like. The collisionavoidance control controls at least one of the steering and thedeceleration in order to assist avoidance of a collision between thevehicle 1 and a surrounding object. The lane departure suppressioncontrol controls the steering in order to suppress the vehicle 1 fromdeparting from a travel lane. When an activation condition of thedriving assist control is satisfied, the vehicle control system 10activates the driving assist control.

As an example of the driving assist control, let us consider thecollision avoidance control. Based on the surrounding situationinformation, the vehicle control system 10 recognizes an avoidancetarget (e.g., a surrounding vehicle, a pedestrian) ahead of the vehicle1. Furthermore, based on the vehicle state information and thesurrounding situation information, the vehicle control system 10predicts respective future positions of the vehicle 1 and the avoidancetarget and calculates a possibility that the vehicle 1 collides with theavoidance target. The activation condition of the collision avoidancecontrol is that the possibility that the vehicle 1 collides with theavoidance target is equal to or higher than an activation threshold.

As another example of the driving assist control, let us consider thelane departure suppression control. For example, when the vehicle 1wobbles within the travel lane and comes close to a lane marking (awhite line) of the travel lane, the lane departure suppression controlperforms the steering so as to make the vehicle 1 return back to acenter of the travel lane. For that purpose, the vehicle control system10 recognizes, based on the surrounding situation information, the lanemarking of the travel lane in which the vehicle 1 is traveling andmonitors a distance between the vehicle 1 and the lane marking. Theactivation condition of the lane departure suppression control is thatthe distance between the vehicle 1 and the lane marking becomes lessthan a predetermined distance threshold.

It should be noted that the vehicle control system 10 includes aprocessor and a memory device in addition to the sensor 20. Theabove-described driving environment information and the like are storedin the memory device. The processing by the vehicle control system 10 isachieved by the processor executing a vehicle control program that is acomputer program stored in the memory device. The vehicle controlprogram may be stored in a computer-readable recording medium.

1-2. Outline of Information Provision System

Furthermore, an information provision system 100 is mounted on thevehicle 1. The information provision system 100 provides a variety ofinformation to an occupant (e.g., a driver) of the vehicle 1.

The information provided to the occupant of the vehicle 1 includes theabove-described driving environment information, a control state of thevehicle 1, a situation around the vehicle 1, an operation demanded ofthe driver, a warning to the driver, and the like. The information isacquired, recognized, or determined by the vehicle control system 10described above. That is to say, the vehicle control system 10 is ableto provide a variety of information to the occupant of the vehicle 1through the information provision system 100. In that sense, theinformation provision system 100 may be a system including the vehiclecontrol system 10. Concrete examples of the information provided throughthe information provision system 100 are as follows.

As a first example, when the vehicle 1 is the automated driving vehicle,“a current automated driving level” is provided as the information. Forexample, the vehicle control system 10 calculates difficulty of theautomated driving control based on the surrounding situationinformation, and dynamically determines the automated driving levelaccording to the difficulty. Alternatively, a feasible automated drivinglevel may be preset for each position or zone and registered in the mapinformation. In this case, the vehicle control system 10 determines theautomated driving level of the vehicle 1 based on the positioninformation and the map information.

As a second example, during the automated driving of the vehicle 1, “thedriver should grab the steering wheel”, that is, “a demand for hands-onof the driver (hands-on demand)” is provided as the information. Asdescribed above, the hands-on zone can be recognized based on thesurrounding situation information or the map information. Therefore, thevehicle control system 10 can determine whether or not to demand of thedriver to hands-on based on the surrounding situation information or themap information.

As a third example, during the automated driving of the vehicle 1, “thedriver is allowed to get hands off of the steering wheel”, that is, “anotification of hands-off to the driver (hands-off notification)” isprovided as the information. The vehicle control system 10 can determinewhether or not the hands-off of the driver is allowable based on thesurrounding situation information or the map information.

As a fourth example, “a warning indicating that the hands-on is notperformed by the driver even though the hands-on is demanded of thedriver” is provided as the information. The vehicle control system 10can determine, based on the driver state information, whether or not thedriver grabs the steering wheel, that is, whether or not the driverstate is the hands-on state.

As a fifth example, “a notification that the driving assist control isactivated” is provided as the information. As described above, thevehicle control system 10 activates the driving assist control when theactivation condition of the driving assist control is satisfied. Thevehicle control system 10 can determine whether or not to activate thedriving assist control based on the activation condition of the drivingassist control and the driving environment information.

As a sixth example, “a pre-warning of activation of the driving assistcontrol” is provided as the information. Based on the activationcondition of the driving assist control and the driving environmentinformation, the vehicle control system 10 can detect that the drivingassist control is likely to be activated, that is, detect a previousstage of the activation of the driving assist control. For example, withregard to the collision avoidance control, a warning threshold lowerthan the above-mentioned activation threshold is set. When thepossibility that the vehicle 1 collides with the avoidance targetexceeds the warning threshold, it is detected as the previous stage ofthe activation of the collision avoidance control.

As a seventh example, “a demand for a braking operation of the driver”is provided as the information. For example, based on the surroundingsituation information, the vehicle control system 10 recognizes apreceding vehicle ahead of the vehicle 1 and calculates a TTC(Time-To-Collision) with the preceding vehicle. When the TTC becomesless than a predetermined threshold, the vehicle control system 10demands of the driver to perform a braking operation.

As an eighth example, “a warning indicating that the braking operationis not performed by the driver even though the braking operation isdemanded of the driver” is provided as the information. The vehiclecontrol system 10 can determine whether or not the braking operation isperformed by the driver based on the vehicle state information.

As a ninth example, when the vehicle 1 is stopped, “a notification thata preceding vehicle ahead of the vehicle 1 starts moving” is provided asthe information. The vehicle control system 10 can detect the start ofthe preceding vehicle based on the surrounding situation information.

As a tenth example, “a notification (warning) that a surrounding vehicle(e.g., a high-speed following vehicle) is approaching the vehicle 1” isprovided as the information. For example, based on the surroundingsituation information, the vehicle control system 10 recognizes afollowing vehicle behind the vehicle 1 and calculates a TTC with thefollowing vehicle. When the TTC becomes less than a predeterminedthreshold, the vehicle control system 10 determines that a high-speedfollowing vehicle is approaching.

The vehicle control system 10 generates an information provision controlsignal CON. The information provision control signal CON includes aninformation provision instruction to the information provision system100 and the information provided through the information provisionsystem 100 (see the first to tenth examples described above). Thevehicle control system 10 outputs the information provision controlsignal CON to the information provision system 100. The informationprovision system 100 receives the information provision control signalCON from the vehicle control system 10. Then, in accordance with theinformation provision instruction, the information provision system 100provides the information included in the information provision controlsignal CON to the occupant of the vehicle 1.

1-3. Configuration Example of Information Provision System

The information provision system 100 according to the present embodimentis configured to “visually” provide the information to the occupant ofthe vehicle 1. A configuration example of the information provisionsystem 100 is also shown in FIG. 1 . As shown in FIG. 1 , theinformation provision system 100 includes a visual device 110, acontroller 120, and an interface 130.

The visual device 110 visually provides the information to the occupantof the vehicle 1. As the visual device 110, a display panel and aluminescent device are exemplified. As the display panel, a liquidcrystal panel, an organic EL panel, and a touch screen are exemplified.As the luminescent device, an LED (Light Emitting Diode) is exemplified.

FIG. 2 is a diagram for explaining an example of the visual device 110and mainly illustrates a dashboard 50 of a vehicle 1. The dashboard 50is a set of parts arranged in front of a driver's seat and a passenger'sseat. For example, the dashboard 50 includes an instrument panel 51, asteering wheel 52, and a glovebox 53. The visual device 110 may beinstalled on the dashboard 50. In that case, the visual device 110 islikely to be included in an effective visual field (i.e., central andperipheral visual fields) of the driver.

For example, a display panel 60 is installed on the dashboard 50. In theexample shown in FIG. 2 , the instrument panel 51 behind the steeringwheel 52 includes a first display panel 61. Moreover, the instrumentpanel 51 between the driver's seat and the passenger's seat includes asecond display panel 62.

FIG. 3 illustrates the first display panel 61 and its peripheral. Thefirst display panel 61 includes a text display portion 61A. Textualinformation is displayed on the text display portion 61A. For example,textual information of “HANDS-ON” demanding of the driver to hands-on isdisplayed on the text display portion 61A.

In the example shown in FIG. 3 , a band-shaped luminescent device 70 isdisposed above the first display panel 61. The luminescent device 70includes a group of LEDs arranged in a band shape. Such the luminescentdevice 70 can provide (represent) different information by emittinglight in different colors. For example, “hands-on demand” is associatedwith a first color, and “hands-off notification” is associated with asecond color that is different from the first color. In this case, theluminescent device 70 represents the “hands-on demand” by emitting lightin the first color and represents the “hands-off notification” byemitting light in the second color.

The shape of the luminescent device 70 is not limited to the band shape.For example, as illustrated in FIG. 4 , the luminescent device 70 may bearranged so as to surround the first display panel 61.

FIG. 5 illustrates the second display panel 62 and its peripheral. Forexample, the map information, the surrounding situation information(e.g., a recognition result by the sensor 20), an operation that isdemanded of the driver (e.g., HANDS-ON), and the like are displayed onthe second display panel 62. In addition, a luminescent device 70 may bearranged so as to surround the second display panel 62.

As another example, the luminescent device 70 may be installed on thesteering wheel 52.

The visual device 110 includes at least one of the display panel 60 andthe luminescent device 70.

As an example other than the dashboard 50, the visual device 110 may beinstalled on a door trim.

The controller 120 (see FIG. 1 ) controls the visual device 110. Moreparticularly, the controller 120 includes a processor 121 and a memory122. Various kinds of information are stored in the memory 122. Theprocessor 121 controls the visual device 110 by executing a controlprogram stored in memory 122. The control program may be recorded on acomputer-readable recording medium.

The controller 120 is communicatively connected to the vehicle controlsystem 10 via the interface 130. The controller 120 receives theinformation provision control signal CON from the vehicle control system10 via the interface 130. The information provision control signal CONis stored in the memory 122.

Then, the controller 120 controls the visual device 110 so as to providethe information included in the information provision control signal CONin accordance with the information provision instruction. When thevisual device 110 is the display panel 60, the controller 120 controlsthe display panel 60 so as to display the information included in theinformation provision control signal CON. When the visual device 110 isthe luminescent device 70, the controller 120 controls the luminescentdevice 70 so as to emit light in a color associated with the informationincluded in the information provision control signal CON.

Hereinafter, the processing by the controller 120 of the informationprovision system 100 according to the present embodiment will bedescribed in more detail.

1-4. Information Provision Processing and Information SwitchingProcessing

As described above, the controller 120 provides the information throughthe visual device 110. This processing is hereinafter referred to as“information provision processing.” The controller 120 also executes“information switching processing” that switches the information to beprovided through the visual device 110. The information before theswitching is hereinafter referred to as “first information.” Theinformation after the switching, which is information different from thefirst information, is hereinafter referred to as “second information.”That is, in the information switching processing, the controller 120switches the providing information from the first information to thesecond information different from the first information. Here, “theinformation being different” means that at least one of a content, atype, a purpose, and a meaning of the information is different.

For example, the controller 120 switches between “the hands-on demand”and “the hands-off notification.” In this case, one of the firstinformation and the second information is “the hands-on demand”, and theother is “the hands-off notification.” For example, when the vehicle 1enters the hands-on zone, the controller 120 switches the providinginformation from “the hands-off notification (the first information)” to“the hands-on demand (the second information).”

As another example, when the automated driving level of the vehicle 1 ischanged, the controller 120 switches the providing information from “theautomated driving level before the change (the first information)” to“the automated driving level after the change (the second information).”

As yet another example, when the previous stage of the activation of thedriving assist control is detected, the controller 120 provides “thepre-warning of the activation of the driving assist control” as theinformation. In this case, the controller 120 switches the providinginformation from another information (the first information) to “thepre-warning of the activation of the driving assist control (the secondinformation).”

As yet another example, when a surrounding vehicle (e.g., a high-speedfollowing vehicle) is approaching the vehicle 1, the informationprovision system 100 provides “the notification that the surroundingvehicle is approaching” as the information. In this case, the controller120 switches the providing information from another information (thefirst information) to “the notification that the surrounding vehicle isapproaching (the second information).”

In this manner, the controller 120 executes the information switchingprocessing in response to a predetermined trigger. The trigger for theinformation switching processing is exemplified by a change in anoperation (e.g., hands-on, hands-off, braking operation) required forthe driver, a change in the automated driving level of the vehicle 1,activation of the driving assist control, detection of the previousstage of the activation of the driving assist control, start of apreceding vehicle, approach of a surrounding vehicle, and so forth. Togeneralize, it can be said that the trigger for the informationswitching processing includes a change in driving environment thatrequires attention of the driver of the vehicle 1.

The trigger for the information switching processing is first recognizedby the vehicle control system 10 described above. Upon recognizing thetrigger, the vehicle control system 10 generates information to be newlyprovided, that is, the information provision control signal CONincluding the second information. Then, the vehicle control system 10outputs the information provision control signal CON including thesecond information to the information provision system 100. Thecontroller 120 of the information provision system 100 newly receivesthe information provision control signal CON and controls the visualdevice 110 so as to provide the second information included in theinformation provision control signal CON. That is, in response to thetrigger, the controller 120 switches the providing information from thefirst information to the second information.

The second information after the switching is likely to be important tothe occupant of the vehicle 1. It is therefore desirable for theoccupant to easily notice the information change from the firstinformation to the second information. For example, when the trigger forthe information switching processing includes a change in drivingenvironment that requires attention of the driver, it is desirable forthe driver to easily notice the information change from the firstinformation to the second information. In particular, during theautomated driving of the vehicle 1, concentration of the driver isdecreased as compared with a case of manual driving, and thus the drivermay overlook the information change.

In view of the above, the present embodiment provides a technique thatcan facilitate the occupant of the vehicle 1 to more easily notice theinformation change. More specifically, the controller 120 executes theinformation switching processing as described below.

FIG. 6 is a conceptual diagram for explaining the information switchingprocessing according to the present embodiment. A horizontal axisrepresents time, and a vertical axis represents a luminance L of thevisual device 110. In a first period P1 prior to a time t1, thecontroller 120 causes the visual device 110 to provide the firstinformation. A time t2 is later than the time t1. In a second period P2after the time t2, the controller 120 causes the visual device 110 toprovide the second information. Therefore, a period from the time t1 tothe time t2, i.e., a period between the first period P1 and the secondperiod P2 is an “information switching period PA” in which theinformation switching processing is performed.

The luminance L of the visual device 110 in the first period P1 is afirst luminance L1. The luminance L of the visual device 110 in thesecond period P2 is a second luminance L2. The first luminance L1 andthe second luminance L2 may be the same, or may be different from eachother. The first luminance L1 and the second luminance L2 each may be afixed value, or may be variably set by a setting operation of the visualdevice 110. Setting values of the first luminance L1 and the secondluminance L2 may be included in the information provision control signalCON.

As shown in FIG. 6 , the controller 120 temporarily decreases theluminance L of the visual device 110 during the information switchingperiod PA. In other words, in at least a part of the informationswitching period PA, the controller 120 sets the luminance L of thevisual device 110 to be a “transition luminance LA” lower than the firstluminance L1 and the second luminance L2. The transition luminance LA=0means that the visual device 110 is temporarily turned off. That is, thecontroller 120 may turn off the visual device 110 in at least a part ofthe information switching period PA.

As described above, according to the present embodiment, the luminance Lof the visual device 110 is temporarily decreased during the informationswitching period PA. Human vision sensitively responds to a differencein the luminance L. Sensitivity to a change in the luminance L is higheven in a peripheral visual field around a central visual field.Therefore, when the luminance L of the visual device 110 temporarilydecreases, the occupant of the vehicle 1 is more likely to give closeattention to the visual device 110. As a result, the occupant of thevehicle 1 can easily notice the change in information provided throughthe visual device 110.

FIG. 7 shows a modification example of the information switchingprocessing according to the present embodiment. A horizontal axisrepresents time, and a vertical axis represents a saturation S of thevisual device 110. The saturation S of the visual device 110 in thefirst period P1 is a first saturation S1. The saturation S of the visualdevice 110 in the second period P2 is a second saturation S2. The firstsaturation S1 and the second saturation S2 may be the same, or may bedifferent from each other. The first saturation S1 and the secondsaturation S2 each may be a fixed value, or may be variably set by asetting operation of the visual device 110. Setting values of the firstsaturation S1 and the second saturation S2 may be included in theinformation provision control signal CON.

As shown in FIG. 7 , the controller 120 temporarily decreases thesaturation S of the visual device 110 during the information switchingperiod PA. In other words, in at least a part of the informationswitching period PA, the controller 120 sets the saturation S of thevisual device 110 to be a “transition saturation SA” lower than thefirst saturation S1 and the second saturation S2. When the saturation Sof the visual device 110 temporarily decreases, the occupant of thevehicle 1 is more likely to give close attention to the visual device110. As a result, the occupant of the vehicle 1 can easily notice thechange in information provided through the visual device 110.

Temporary decrease in at least one of the luminance L and the saturationS of the visual device 110 brings about the effect. Both the luminance Land saturation S of the visual device 110 may be temporarily decreased.

FIG. 8 is a flow chart summarizing the information provision processingand the information switching processing according to the presentembodiment.

In Step S100, the information provision system 100 (i.e., the controller120) provides information through the visual device 110. The informationprovided in the Step S100 is the first information.

In Step S200, the vehicle control system 10 determines whether or notthe trigger for the information switching processing occurs. When notrigger occurs (Step S200; No), the processing returns to Step S100. Onthe other hand, when the trigger occurs (Step S200; Yes), the processingproceeds to Step S300.

In Step S300, the vehicle control system 10 outputs information to benewly provided, that is, the information provision control signal CONincluding the second information to the information provision system100. The information provision system 100 receives a new informationprovision control signal CON. The information provision system 100receives the new information provision control signal CON.

In subsequent Step S400, the information provision system 100 (i.e., thecontroller 120) executes the information switching processing. That is,the information provision system 100 switches the information providedthrough the visual device 110 from the first information to the secondinformation. During the information switching processing, theinformation provision system 100 temporarily decreases at least one ofthe luminance L and the saturation S of the visual device 110. In otherwords, the information provision system 100 sets at least one of theluminance L and the saturation S of the visual device 110 to be lowerthan that in the first period P1 and the second period P2.

When the information switching processing is completed, the processingreturns to Step S100. The second information after the switching becomesnew first information.

1-5. Concrete Example

Hereinafter, a concrete example of the information provision processingand the information switching processing will be described. In theconcrete example, the vehicle 1 is an automated driving vehicle, and thevisual device 110 includes the luminescent device 70 (see FIGS. 3, 4,and 5 ). The luminescent device 70 can provide (represent) differentinformation by emitting light in different colors. In the concreteexample, the luminescent device 70 represents the “hands-on demand” andthe “hands-off notification” distinctively by emitting light indifferent colors. A color associated with the “hands-on demand” ishereinafter referred to as a “hands-on color.” On the other hand, acolor associated with the “hands-off notification” is hereinafterreferred to as a “hands-off color.”

FIGS. 9 and 10 are flow charts showing the concrete example. First, theflow shown in FIG. 9 will be described. At a start of the flow shown inFIG. 9 , the vehicle 1 is located in a zone other than the hands-onzone, and the hands-off of the driver is allowed.

In Step S510, the controller 120 of the information-provision system 100causes the luminescent device 70 to emit light in the hands-off color.This Step S510 corresponds to Step S100 (information provisionprocessing) in FIG. 8 .

In subsequent Step S520, the vehicle control system 10 determineswhether or not it is necessary to demand of the driver to hands-on. Forexample, when the vehicle 1 is located within the hands-on zone or islikely to enter the hands-on zone, the vehicle control system 10determines that it is necessary to demand of the driver to hands-on.This Step S520 corresponds to Step S200 in FIG. 8 . When the hands-ondemand is not necessary (Step S520; No), the processing returns to StepS510. On the other hand, when the hands-on demand is necessary (StepS520; Yes), the processing proceeds to Step S530.

In Step S530, the vehicle control system 10 instructs the informationprovision system 100 to provide the “hands-on demand.” That is, thevehicle control system 10 instructs the information provision system 100to switch from the hands-off color to the hands-on color. This Step S530corresponds to Step S300 in FIG. 8 .

In subsequent Step S540, the controller 120 of the information provisionsystem 100 executes color switching processing that corresponds to theinformation switching processing. More specifically, the controller 120temporarily decreases at least one of the luminance L and the saturationS of the luminescent device 70. Subsequently, the controller 120 changesthe color of the luminescent device 70 from the hands-off color to thehands-on color. After that, the controller 120 restores the luminance Land the saturation S of the luminescent device 70. This Step S540corresponds to Step S400 in FIG. 8 .

In Step S550, the controller 120 causes the luminescent device 70 toemit light in the hands-on color.

In Step S560, the vehicle control system 10 determines, based on thedriver state information, whether or not the driver grabs the steeringwheel, that is, whether or not the driver state is the hands-on state.If the driver state is not the hands-on state (Step S560; No), theprocessing proceeds to Step S570.

In Step S570, the vehicle control system 10 instructs the informationprovision system 100 to issue a warning to the driver. In response tothe instruction, the controller 120 of the information provision system100 issues a warning to the driver. For example, the controller 120causes the luminescent device 70 to blink in the hands-on color. Then,the processing returns to Step S560.

When the driver state becomes the hands-on state (Step S560; Yes), theprocessing proceeds to the flow shown in FIG. 10 .

In Step S610, the controller 120 of the information-provision system 100causes the luminescent device 70 to emit light in the hands-on color.This Step S610 corresponds to Step S100 (information provisionprocessing) in FIG. 8 .

In subsequent Step S620, the vehicle control system 10 determineswhether or not the hands-off is allowable. For example, when the vehicle1 is located in a zone other than the hands-on zone, the vehicle controlsystem 10 determines that the hands-off is allowable. This Step S620corresponds to Step S200 in FIG. 8 . When the hands-off is not yetallowable (Step S620; No), the processing proceeds to Step S660. On theother hand, when the hands-off is allowable (Step S620; Yes), theprocessing proceeds to Step S630.

In Step S630, the vehicle control system 10 instructs the informationprovision system 100 to provide the “hands-off notification.” That is,the vehicle control system 10 instructs the information provision system100 to switch from the hands-on color to the hands-off color. This StepS630 corresponds to Step S300 in FIG. 8 .

In subsequent Step S640, the controller 120 of the information provisionsystem 100 executes color switching processing that corresponds to theinformation switching processing. More specifically, the controller 120temporarily decreases at least one of the luminance L and the saturationS of the luminescent device 70. Subsequently, the controller 120 changesthe color of the luminescent device 70 from the hands-on color to thehands-off color. After that, the controller 120 restores the luminance Land the saturation S of the luminescent device 70. This Step S640corresponds to Step S400 in FIG. 8 .

In Step S650, the controller 120 causes the luminescent device 70 toemit light in the hands-off color. After that, the processing proceedsto the flow shown in FIG. 9 .

In Step S660, the vehicle control system 10 determines, based on thedriver state information, whether or not the driver state is maintainedat the hands-on state. When the driver state is maintained at thehands-on state (Step S660; Yes), the processing returns to Step S610. Ifthe driver state is not the hands-on state (Step S660; No), theprocessing proceeds to Step S670.

In Step S670, the vehicle control system 10 instructs the informationprovision system 100 to issue a warning to the driver. In response tothe instruction, the controller 120 of the information provision system100 issues a warning to the driver. For example, the controller 120causes the luminescent device 70 to blink in the hands-on color. Then,the processing returns to Step S660.

1-6. Effects

As described above, the information provision system 100 according tothe present embodiment provides information to the occupant of thevehicle 1 through the visual device 110. The first information isprovided in the first period P1, and the second information is providedin the second period P2 later than the first period P1. In theinformation switching period PA between the first period P1 and thesecond period P2, the information switches from the first information tothe second information. In at least a part of the information switchingperiod PA, the information provision system 100 sets at least one of theluminance L and the saturation S of the visual device 110 to be lowerthan that in the first period P1 and the second period P2. In otherwords, the information provision system 100 temporarily decreases atleast one of the luminance L and the saturation S of the visual device110 during the information switching period PA. At this time, due to thevisual property of human, the occupant of the vehicle 1 is more likelyto give close attention to the visual device 110. As a result, theoccupant of the vehicle 1 can easily notice the change in informationprovided through the visual device 110.

As a first comparative example, let us consider a conventional techniquedescribed in Patent Literature 1. According to the conventionaltechnique, the image displayed on the display means merely changes fromthe first image representing the information before the change to thesecond image representing the information after the change. Therefore,it is difficult for the occupant to notice the information change.

As a second comparative example, notifying the information change by analarm is considered. However, if the alarm is sounded every time theinformation changes, the occupant feels annoyed. On the other hand,according to the present embodiment, it is possible to facilitate theoccupant to easily notice the information change without sounding thealarm. Therefore, the occupant's sense of annoyance is reduced.

The visual device 110 may be installed on the dashboard 50. In thatcase, the visual device 110 is likely to be included in an effectivevisual field (i.e., central and peripheral visual fields) of the driver.Therefore, the driver can further easily notice the information change.

During the automated driving of the vehicle 1, concentration of thedriver is decreased as compared with a case of manual driving, and thusthe driver may overlook the information change. Therefore, theinformation switching processing according to the present embodiment maybe advantageously applied to the automated driving vehicle.

2. Second Embodiment

In a second embodiment, the controller 120 of the information provisionsystem 100 gives a warning to the driver of the vehicle 1 by causing thevisual device 110 to blink. It should be noted that the visual device110 in the second embodiment is exemplified not only by the displaypanel 60 and the luminescent device 70 but also by a room lighting andthe like.

FIG. 11 is a flow chart showing the information provision processingaccording to the second embodiment.

In Step S710, the vehicle control system 10 determines whether or notthere is an operation expected of the driver. For example, when thevehicle 1 is located within the hands-on zone, the driver is expected tograb the steering wheel, i.e., the hands-on state is expected. Asanother example, when the TTC with the preceding vehicle becomes lessthan a predetermined threshold, the driver is expected to perform abraking operation. When there is an operation expected of the driver(Step S710; Yes), the processing proceeds to Step S720.

In Step S720, the vehicle control system 10 determines whether or notthe operation expected of the driver is actually performed by thedriver. For example, the vehicle control system 10 can determine, basedon the driver state information, whether or not the driver grabs thesteering wheel, that is, whether or not the driver state is the hands-onstate. As another example, the vehicle control system 10 can determinewhether or not the driver performs the braking operation based on thevehicle state information. When the operation expected of the driver isnot actually performed (Step S720; No), the processing proceeds to StepS730.

In Step S730, the vehicle control system 10 instructs the informationprovision system 100 to issue a warning to the driver. In response tothe instruction, the controller 120 of the information provision system100 issues a warning to the driver. More specifically, the controller120 causes the visual device 110 to blink. Then, the processing returnsto Step S720.

When the operation expected of the driver is actually performed (StepS720; Yes), the processing returns to Step S710.

As described above, according to the present embodiment, when theoperation expected of the driver is not performed by the driver, theinformation provision system 100 causes the visual device 110 to blink.The blinking of the visual device 110 applies stimulus to the driver'svision. It is thus possible to urge the driver to pay attention.

What is claimed is:
 1. An information provision system mounted on avehicle and comprising: a visual device configured to visually provideinformation to an occupant of the vehicle; and a controller configuredto control the visual device, wherein the controller is furtherconfigured to: cause the visual device to provide first information in afirst period; and cause the visual device to provide second informationin a second period later than the first period, the second informationbeing different from the first information in at least one of a content,a type, a purpose, and a meaning, wherein at least one of a luminanceand a saturation of the visual device in the second period is differentthan in the first period.
 2. The information provision system accordingto claim 1, wherein the visual device is installed on a dashboard of thevehicle.
 3. The information provision system according to claim 1,wherein the visual device represents the first information in a firstcolor and represents the second information in a second color differentfrom the first color.
 4. The information provision system according toclaim 1, wherein the vehicle is an automated driving vehicle thatperforms automated driving.
 5. The information provision systemaccording to claim 4, wherein one of the first information and thesecond information is information demanding of a driver of the vehicleto grab a steering wheel during the automated driving, and another ofthe first information and the second information is informationnotifying that the driver is allowed to get hands off of the steeringwheel during the automated driving.
 6. The information provision systemaccording to claim 1, wherein in response to a trigger, the controllerswitches the information provided through the visual device from thefirst information to the second information, and the trigger includes achange in driving environment that requires attention of a driver of thevehicle.
 7. The information provision system according to claim 6,wherein the trigger includes at least one of a change in an operationrequired for the driver, a change in an automated driving level of thevehicle, activation of driving assist control that assists driving ofthe vehicle, detection of a previous stage of the activation of thedriving assist control, start of a preceding vehicle, and approach of asurrounding vehicle.
 8. The information provision system according toclaim 1, wherein the visual device includes a luminescent device havinga plurality of LEDs, and the luminescent device represents differentinformation by emitting light in different colors.
 9. The informationprovision system according to claim 8, wherein the plurality of LEDs ofthe luminescent device are arranged in a band shape.
 10. The informationprovision system according to claim 8, wherein the visual device furtherincludes a display panel, and the plurality of LEDs of the luminescentdevice are arranged so as to surround the display panel.